I have a crack in the exhaust on our M5, where is the best polace to get replacements, I am thinking I would replace both sides

John: My best source has always been having one repaired or replaced by Dawley Aviation here in the states. They will take a bad unit and basically build a new one and can call it a repair. I have had better luck with their units than with the factory ones... I have no idea what the turn time would be for delivery "down under" to you. They are on the internet... Good luck.

Given that they all crack eventually, even new ones or Dawley "repaired" ones, I choose instead to have mine repaired by a local welder. Every year or two, a new small crack (or a few) starts to develop and I need to pull them to get them repaired, but each time it only costs me maybe $60 instead of $1000 or more. Of course, all of my cracks have been in flanges; none into the main muffler shell itself.

John: I would agree with Andy if the cracks are manageable and you have access to an accomplished welder with TIG welding capability that is a good alternate. I have in fact done that myself. Over time with wear and tear and metal fatigue sometimes a new muffler or a major repair is warranted. Make sure your tail pipes have some movement in them and are hanging off the lower firewall on the straps... This exhaust system is less than ideal as has been discussed here on many occasions.

I bought a new set from Atlee Dodge in Anchorage. They have a different design where the fore and aft header pipes are fixed and only the center header "slips"...and it makes sense. The mufflers have "heat sink" fins that transfer heat for cabin and carb heat and also stiffen the muffler. Within hours of ordering, they were preparing for shipment. When you weld a crack and heat the metal up it gets more brittle and is more susceptible to cracking again. The other important issue are the flame tubes inside the muffler which can prevent a fire if the engine backfires while starting a hot or flooded engine.

I stock the Atlee set up and won't go anywhere else. PMA Direct replacement and MUCH better heat and flow with lager dia. pipes, Total Win Win

I have a cracked muffler, does anyone know what filler wire works best to do the repair
Thanks
Gary

Does anyone know what material the mufflers are made from?
Thanks
Gary

Usually 321 or 304 stainless steel. 321 is more expensive but has better high temperature fatigue resistance. Atlee Dodge's PA-18 Heavy Duty Muffler uses 321: https://fadodge.com/pa-18-heavy-duty-muffler/

I believe Maule uses 304 stainless steel for their mufflers. Maybe Duane can confirm that.

Thanks Andy
It looks like 347 filler rod is best for 304, 304L or 321